Website Migrations for SEO: Why they’re more than just 301 re-directs

I’ve been involved in my fair share of website migrations over the years. Whether that’s been as an account executive, account manager, project manager, campaign manager, or SEO strategist.

Even during my first months into my digital marketing career back in 2015, I was thrown straight into project management as it was a great way to learn everything about website builds and migrations.

I’ve learnt a hell of a lot about migrating a website for SEO over the past 6 and a half years, whether it’s migrating from one CMS to another, a complete re-build, or just a re-skin of the front end, the one thing that has been consistent across all of them is the lack of understanding from a website owner/marketer on the importance any re-build or migration is for SEO.

It does not matter if your website is e-commerce or more of a brochure site, any website is one of the most, if not the most important marketing tool for any business. It could be sales, newsletter sign-up, or enquiries, there is always a goal/revenue associated with any website, and if you do not involve an SEO in the re-build or migration process, the results can be very harmful to your business.

Within this guide, I’ll talk you through why it’s important, what I have learnt along the way, and my tips on how to get website migrations right for SEO.

What does migrating a website mean?

It might seem obvious to some, but it’s important to start here. So what does migrating a website actually mean? Don’t worry, your website isn’t not leaving the country, far from it!

A website migration is a term that’s widely used by SEO and Digital Marketing professionals to describe any activity in which a website goes through substantial changes that can potentially positively or negatively affect search engine visibility. This could be anything from a brand new platform, a new site structure, new content, or a brand new design.

Types of Site Migrations

There are many different types of site migrations, but almost all website migrations fall into these categories:

Site location changes

These are types of migrations where a site moved from one URL to another URL. It’s worth explaining that this does not necessarily mean a simple domain name change.

Site protocol changes

The most common example of this is when a site moves from HTTP to HTTPS.

If you’ve not planned a site protocol change right, it’s likely your site could be negatively impacted in the organic search results. You might be aware that Google gives secure sites that have the secure HTTPS protocol a lightweight ranking signal boost, but simply obtaining an SSL certificate and moving over to HTTPS isn’t enough. You need to ensure that your website developer completes this HTTPS migration checklist:

  • Install an SSL certificate
  • Add the HTTPS version to search console
  • Set up 301 redirects of all HTTP instances to redirect to HTTPS
  • Change all internal links from HTTP to HTTPS
  • Check and fix any mixed content issues

Subdomain change

The most common subdomain change is when you’re moving a section of a website, or series of pages from a subdomain to a subfolder. One of the most common examples would be to move a blog from a subdomain to a sub folder e.g. https://blog.yoursite.com to https://yoursite.com/blog.

Another example could be if a website has a separate mobile version to the desktop version. A mobile version is typically https://m.yoursite.com, and it’s not uncommon for websites that are not fully responsive to have separate mobile subdomains. Then when the whole site is made responsive, the mobile subdomain is migrated away, as all URLs will now be the same across mobile and desktop.

Domain name change

This is less common but happens when companies go through a re-brand process and there is a need to change the domain name.

Top-level domain change

Again, this is less common compared with protocol and subdomain changes, and generally happens when a company might want to, for example, change their website from a .co.uk to a .com top-level domain.

Site Platform Changes

These are the migrations that I have worked on more than any other, and often are combined with other migrations such as sit structural changes, content, and design changes.

Usually, when a company is going through the process of a site platform change, their site CMS/Platform may no longer be fit for purpose, or their platform may be due a major version update that requires a re-build.

This usually gives marketers the chance to also refresh the website, with a new updated design/look and feel, and updated content. It is under these circumstances where involving an SEO from the beginning of your project is much more critical.

Moving from one CMS platform to the other

Maybe your business has outgrown the CMS in which the foundations of the business were started, maybe you’re changing from a bespoke solution to an open-source solution, or maybe you’ve just fallen out of favour with your development agency and your new chose agency doesn’t support your current CMS. Either way, this means you need to migrate away from one CMS platform and re-build your website onto another CMS platform.

Upgrading from one platform version to another

This often happens when an open-source platform, like Magento or Umbraco, updates from one major version to another. If you want to upgrade from the old major version to the latest major version, this almost always means you have to re-build your back end CMS from the ground up in the newest version.

It could also be that you’re on an older version that is no longer supported, for example, this has happened recently with the announcement from Magento that support for Magento 1 would be no longer supported from 30th June 2020. This has lead to a rush of e-commerce owners needing major version upgrades from Magento 1 to Magento 2.

Content changes

This one might not seem like a type of migration at first, but content changes can be classed as a form of migration.

Have you introduced a new language/local version of your website, or are you going through a content audit and consolidating pages and content together?

In these circumstances, you are migrating content from one place to another place, and when not done properly, can have negative effects on your organic search rankings.

Site Structural Changes

Site structural changes often happen during major projects such as website re-builds, platform changes, and major design or UX changes. There are different ways in which a site structure can change.

Site hierarchy & Navigation changes

A site hierarchy is the list of links that allow a user to navigate through a website, and is most commonly seen in top-level menus, found in site headers on desktop, and often behind a burger menu on mobile, and less commonly found in sidebars, and footers.

Any major changes to the site hierarchy often means migrating content from one subfolder (URL structure) to another one. This often happens during a re-design or as part of major UX changes.

Internal linking changes

Internal linking is something that is often completely overlooked, but is one of the most important elements to any good SEO strategy.

The way in which Google crawls and indexes websites is by following links, whether thats internal or external links, so ensuring you have a good internal linking structure is vital to make sure all the pages on your website are found, understood, and indexed by Google.

So it is important that when there are internal linking changes, they’re done right.

Design or UX changes

Changes to the design or UX of a website or page often ultimately means that there could be changes to the websites site structure, internal linking, content, and site hierarchy. So if you’re planning on making some page template design changes, even if they are look and feel changes, do not overlook the fact that you’ll need to engage with an SEO professional as part of the process.

Why are website migrations important for SEO?

Putting it simply, when a website migration is done badly, a websites organic search visibility can diminish or even drop off. When organic search is one of the most important marketing channels for any business, you simply cannot afford to rush a website migration.

Less organic search visibility almost always means less website traffic, which in turn can lead to less sales for your business.

Re-directs are still critical to any website migration

Redirects are still critical, without them your website would drop off a cliff. Re-directs are essential to inform Google that the old page URL is no longer available, and they should index the new URL in which it redirects to. Redirects are also critical to ensuring that there are no broken links throughout a customer user journey.

Redirects make it much quicker for Google to discover, index and understand the new page/content that you’re looking to replace, also allowing any ranking signals to pass from the old pages to the new ones, which is also vital in retaining rankings. When doing redirects, take time to consider what the best match is when redirecting an old URL to a new URL. If, for whatever reason, there is no longer a page with the exact same content, consider what content/page might be the best to topically align, or what might simply be the best match.

Pro Tip

When doing redirects, take time to consider what the best match is when redirecting an old URL to a new URL. If, for whatever reason, there is no longer a page with the exact same content, consider what content/page might be the best to topically align, or what might simply be the best match.

This ensures when reindexing, Google understand how the old page content fits in with the new page content.

What happens when redirects are not properly implemented?

Not implementing redirects properly can be deadly. Your users will either land on 404 page not found pages from external links, or users land on pages that are completely irrelevant and do not meet the intent of what they were looking for.

The consequences of this will be higher bounce rates, poor user experience, less traffic, and most importantly, from Googles perspective, they’ll be unable to connect the old site pages to the new site pages, and ranking signals will be lost resulting in ranking drops.

You need to consider more than just redirects

As the blog title states, there’s more to migrations than just doing redirects. There are other considerations that are important to ensure you do not lose rankings.

Make sure there isn’t any missing content

I’ve seen this time and time again during site platform changes, site structural changes, and design or UX changes. Where a website is re-designed from the ground up, and the project leads have not considered the existing site structure and content from an early stage, resulting in content that no longer fits into the new site structure. Or simply just not migrating old blog posts over from the old website to the new website when undergoing site platform changes.

When there is missing content, there are typically two main risks:

  1. You may lose out on any rankings that content may have had, resulting in losing organic search traffic
  2. The page content could have played an important role as a supporting page to a main pillar or topic. Losing the page content could result in thinning out the topical authority of a main topic/ or pillar on your website.

Content is king when it comes to SEO. Ultimately, Google wants to serve the very best content that best matches a users search query, so your site content has to be considered as a critical part in any website migration from the very start.

Make sure you do not remove internal links

Your internal links important not only to help users navigate throughout your site, but are also helping to either pass page rank throughout your site, or to pass topical authority.

It’s also important to remember that Google bot discovers and crawls pages by following links, so ensuring you have a good site structure, with internal linking ensures that pages do not get lost when Google bot crawls your website.

If you’ve undergone a re-design, and you’ve not included internal linking within the new page designs, for example, a side navigation within the blog that internally links to related blogs or pages, then this can immediately halt any internal linking benefits. Without internal links, a page is effectively a dead end. Not only can you end up missing out on passing page rank throughout your site, but you can worsen the topical authority.

Common SEO migration mistakes

So now you hopefully understand the importance of site migrations, and if you’re reading this and considering a site migration in the near future, I’ve set out some of the common SEO migration mistakes I have experienced and seen throughout my digital marketing career to date.

Poor strategy/planning

There needs to be a clear plan in place for any website migration, and arguably there should be a project manager in charge of the migration, especially during site platform changes, site structural changes, and design or UX changes.

Pro Tip

Make sure there is a clear strategy or set of goals drawn up and agreed by all parties before the start of the project. A website migration with no clear goals is much more likely to fail.

You need to set clear and realistic objectives from the start, for example, one of the primary objectives should be to maintain the sites organic traffic and revenue. Setting clear goals and objectives before the projects starts will ensure that you can properly plan the project.

The project planning should include everything from mapping the site structure, wireframes, designs, functional specifications, development, content, testing, hosting, as well as the migration itself. Be flexible with your plan and ensure that you have adequate time in for sign offs at key milestones, and factor in for delays. There should also be a series of key milestones and sign off points for stakeholders so they’re aware of the points and times during the project where they’ll be needed.

Also be aware of any seasonal peaks, and avoid any migration during busy or important seasonal periods for your clients websites. For example, I’d highly recommend not going live on a website migration for an e-commerce website in the lead up or close to Christmas.

If the planning has been done without any clear objectives, rushed, skipped altogether, or missed vital milestones, it often results in a delayed or poor website migration.

Not consulting with an SEO

I honestly cannot tell you how important this is, if you do not consult or involve an SEO within your migration project, you run a high risk of missing a key element to ensure your migration does not have a long term adverse effect on your organic rankings and traffic.

If you do not have an in house SEO person within your organisation, or the agency you’re engaging with does not have an SEO expert, I would highly recommend looking for a freelance SEO consultant who has experience with website migrations.

Late involvement from an SEO

Asking the SEO person within your organisation or agency to take a look at the project at a late stage is something I’ve seen happen a lot, and in the early stages of my career, I have also been victim to doing this.

Bringing in an SEO expert at the end, or late on in the project will undoubtedly result in the SEO expert requiring to make changes to the website project to ensure there is no mitigating risk to losing organic positions and traffic. This will extra add additional time and budget to the project, and as is often the case late into a project, the project manager has already exhausted the buffer within the budget that was set aside at the beginning of the project.

What ends up happening is the client either says they don’t have the extra budget, are unwilling to pay for the extra budget/costs, or agree to do the work as part of a “phase 2” so not to move back the website migration launch date.

By involving an SEO from the start of a project, you will avoid unnecessary delay, budget, stress, and most of all you are mitigating any risk in losing organic rankings and traffic after the migration is complete.

Poor testing/bug fixing

It’s really important to dedicate a good chunk of time to properly test and fix bugs before any website migration goes live. You would much rather delay a website migration go live after finding a critical issue, than skipping/rushing the testing phase to discover that there was an avoidable issue that is now holding back your website.

It’s also advisable to have an SEO and UX designer to also be involved in the testing phase, as well as the wider project team. A go live should certainly not be going live without an SEO sign off as part of the approval process.

Under-estimating the scale of the task

In almost every website project I have been involved in with a new client has resulted in the client seriously under estimating how the website project/migration will be so time consuming, and the level of work needed from their part.

Do not fall into the trap of sticking to a planned go live date, even if the website migration is not ready. It’s far too easy to say let’s go live and we’ll pick up the remaining work as a phase 2, but all it takes is a couple of weeks of the clients website to lose rankings and suddenly their losing traffic and revenue which could take months to recover.

Likewise, if an agency tells you as a website owner that a new website project for a change in platform, UX redesign, or major site structural change will take 3 months from start to finish, you should double that time as the agency has under-estimated the website owners time needed, as well as under-estimated time for any unexpected issues.

The tools you’ll need for SEO migrations

There are lan array of online tools available that will make your job much easier when undertaking a website migration project. I’ve highlighted below some of the tools that I have used throughout my time as a project lead, or supporting the project lead with a website SEO migration.

Slickplan – For building sitemaps

Getting the site structure mapped out at the beginning of a website project is important to ensure you capture every possible page template, and that the content and migration is correctly mapped out for SEO. One of mu favourite tools to use for this is the sitemap builder in slickplan.

The site map builder is has an intuitive easy to use drag and drop system, where you can effortlessly create, customise, share, and integrate your sitemaps into project management tools like Basecamp and Slack.

The collaboration tool is also very handy if you need to collaborate with different internal teams, or with your external client.

There is a 30 free trial, and should you sign up after your trial period has ended, there are 4 account options to suit different businesses and budgets, with plans starting from $8.99 per month.

If you’re looking for an easy to use free tool, I’d recommend GlooMaps. It’s a super easy and fast way to quickly put together a site map, but as it’s free, you cannot use this to collaborate with different people. Only you as the user can edit the site map.

Screaming Frog – For crawling websites

Having the ability to crawl all of the websites pages is not only important so you do not miss any content as part of the migration, but you can also obtain each pages title tag, meta description, and headings, to ensure that cotnent is migrated over as close to as possible as the old website.

Screaming Frog is the tool you need for this, their powerful website crawler is so customisable, as an SEO you can do almost anything with the tool. As part of SEO migrations, Screaming Frog is ideal for things like:

  • Getting a list of all pages on a website
  • Get information on all of the internal links on a website
  • Find broken internal links
  • Find images that are missing alt text
  • Identify duplicate content
  • Identify thin content
  • Create an XML sitemap
  • Check what areas of a website are not being indexed, and why
  • Find page speed issues
  • Scraping meta data

Seer interactive have put together a really in depth guide on how to do almost anything in Screaming Frog, so make sure you bookmark their guide in your browser.

Screaming Frog also has the ability to integrate with Google Analytics, Google Search Console, and Ahrefs, so you can pull in information like sessions, impressions, clicks and backlinks into your website crawl.

Semrush – For keyword research

I’d advise to undertake keyword research during a website migration project, conducting thorough keyword research gives you the best possible base layer to ensure you’re targeting the right keywords for your key topics and supporting content across all of your pages.

The Semrush keyword research tool is my preferred keyword research tool to use, not only does it give you the ability to analyse your competitors keywords, find gaps and discover new opportunities, but has a user-friendly keyword magic tool, which helps you identify the best keyword to match the intent of the topic or content on your website.

You can then analyse and export 1,000 keywords at once, and see changes within the SERP features or top ranking competitor for each keyword in real time.

Ahrefs – For backlink audits

The ability to check your web pages for backlinks is important so you do not lose any page rank that the backlinks will be distributing throughout your website, and the ahrefs backlink tool is my preferred choice.

As well as checking your pages for backlinks, it also has a great internal linking tool, giving you the ability to check what internal links are incoming and outgoing on a page of your website. This is handy to check for future internal linking opportunities.

Other tools you’ll need

There are going to be many other tools along the process which you’ll need as part of any website migration, specifically to aid SEO, here are some further tools you’ll need.

Make sure you have access to your clients Google Analytics and Google Search Console accounts. Both GA and GSC can give you invaluable statistics which can help you determine site structure, highlight potential issues, and most importantly, give you up to date traffic and user statistics which will be invaluable during the migration.

I could not survive without Google Sheets, if you’re not familiar with Google Sheets, it’s essentially a free online version of Microsoft Excel, which also allows you to collaborate and share with others live. You can also export them to Microsoft Excel formats, as well as upload Excel sheets into Google Sheets. I use Google Sheets for many tasks, such as:

  • Keyword Research
  • Creating Checklists
  • Creating Roadmaps
  • Technical SEO audits
  • Development work backlogs

You’ll also probably need something to manage all of your tasks and to keep on top of your time keeping, for this I use Trello. Trello is a kanban board which allows you to create cards within a board, and set out a series of columns which the cards can then flow through as a process. I would set up each major task as a card, set due dates and a priority, and move these through a process, for example, To-Do, Doing, With Client, Completed etc.

You can easily add other people to your board, collaborate, share and communicate with other users to keep them up to date on progress of each task.

Trello is ideal for freelancers, as well as small to medium businesses, and best of all, you can have up to 8 personal boards for free!

My tips for a successful SEO migration

Here are my top tips for a successful SEO migration I wish I had known when I was first starting out in the industry. This is by no means an extensive list, and there is plenty of resources out there to provide further help and support. Some areas for great resources are moz blog, search engine land, semrush blog, search engine watch, and search engine journal.

Make an SEO migration checklist

Santa makes a list and checks it twice for a reason, he needs to stay organised. So you should probably do the same. Creating an SEO migration checklist/plan from the start of a project to help keep the migration on track, completed on time, and to work towards the agreed goals that were set out before the project started.

As an outline, your checklist should include, but not limited to:


  • An agreed target date for the migration, that everyone is working towards
  • Compiling a list of all URLs on the current website
  • Compile top level visit stats for the main entrances pages of your website, for benchmarking
  • Compile backlink stats for each URL
  • Take an export of the current meta titles, descriptions, and H1 tags
  • Benchmark the current rankings and organic traffic
  • Compile a list if all the internal links per page type/template to ensure these are carried over onto the new site
  • Compile a list of all the URLs planned for the new site
  • Make a copy of the robots.txt file
  • Back up your existing content
  • Create a sitemap of the new website
  • Ensure any staging site has NOINDEX, NOFOLLOW implemented on all pages
  • Map the old URLs to the new URLs
  • Map existing redirects to point to the new website
  • Check the new website is mobile friendly, and mobile has the same user experience as desktop
  • Carry over internal linking from the old site to the new site
  • List all of the current schema in place across the current site and ensure this is transferred to the new site
  • List any canonical logic and make sure it is carried over to the new site
  • List any NoIndex logic and make sure it is carried over to the new site
  • List any tracking codes and make sure it is carried over to the new site


  • Set 301 redirects
  • Check redirects match with the desired location
  • Fix any broken redirects
  • Run a crawl of the new website
  • Check internal links are carried over
  • Check all pages have a 200 status code
  • Check for orphaned pages
  • Update any internal 301 redirects
  • Fix any 404 pages
  • Check for any internal links going to a staging site
  • Check and ensure meta data and H1 tags are carried over, and fix any missing
  • Check canonicals are correctly referenced
  • Check tracking codes are copied over
  • Check schema has been copied over
  • Check images are optimised
  • Check for duplicate content
  • Check XML sitemap contains all pages
  • Check any NOINDEX, NOFOLLOW tags have been removed
  • Submit the new XML sitemap to Google Search Console
  • Check the robots.txt file is the same
  • Check the 404 page is working

Perform a technical SEO audit pre and post migration

This is an absolute no brainer in my view. Performing an audit pre and post migration means you can compare the two audits to ensure no issues have been carried over, and if they have, you can quickly highlight these to the developers and get them fixed.

Pro Tip

Run a crawl of the test/staging site before any planned launch, during the testing phase, so you can spot and fix any issues before the planned migration go live date. This ensures the website is in the best possible position ahead of the migration.

Plan to launch during a slow period

Check with your client, and within their google analytics what would be the best period for a migration go live. What period is seasonally quiet where we can ensure impact minimised.

Do this right at the begging of the project, and also check if there are any notable planned holidays for anyone within the project and the client leads that would not impact on any key milestones or planned go live date.

Set a buffer of time within any project timeline/plan to account for any unexpected issues

There will no doubt be something unexpected throughout the process, so plan ahead for this and set extra time aside to deal with any unexpected issues, longer than expected bug fixes, or any unexpected holidays or sick leave. Doing this will ensure that the project does not go behind schedule, and the best case scenario is that you’ll end up being ahead of schedule.

Make sure everyone knows what they’re doing in the project team

Make sure, as part of your planning that everyone within the project team has tasks assigned to them with due dates. Each task needs to be fully briefed in ahead of time to ensure those undertaking the tasks know exactly what is expected of them.

Planning ahead and doing this early on will save more project management time in the long term.

Make sure an SEO is involved from the start

And finally, really do make sure you have an SEO person involved in the website migration project from the very start, also ensuring they are part of the sign off process for each key milestone.

An SEO expert can help you set the defined goals, set benchmarks from the existing